Desktop application – used to build a custom XAP package with 5 custom ringtones you select from your computer(Required .NET 4.0 Framework)
XAP application – to be deployed to your WP7 to install custom ringtones to the system
Notes

Ringtones have to be in the WMA format at 48KHz as required by the OS. We recommend using Expression Encoder 4 (free) to transcode any MP3s.
Currently, to deploy the XAP you will have to use the Microsoft “Application Deployment” tool with the Windows Phone 7 Developer SDK. In the future, we hope to make available a standalone deployment solution for homebrew apps.

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